The invention relates to a method of controlling a warp beam drive of a weaving machine in which the warp beam drive speed is proportional to a value governed by the number of rotations of the warp beam and the tension of the warp thread, and to a device for carrying out the method which includes a control for influencing the warp beam drive, and a device for measuring the tension of the warp threads and generating a signal to the control.
Such a method, as well as a suitable device for carrying out the method, is disclosed in German Pat. No. 29 39 607. There, the tension of the warp threads is measured by the position of a dancer, and the number of revolutions of the warp beam is recorded by means of a driving pinion. Both measurements are supplied to a controller or regulator, which controls a driving unit that drives the warp beam at a predetermined speed.
The aforementioned device does not deliver satisfactory weaving results, particularly when the warp beam is started up from a stationary condition. In such instances, so-called "stop marks" or "start marks" are formed in the woven fabric. This flaw originates from the fact that the dancer is inclined to overswing or over-shoot on starting up and therefore no longer delivers any usable or rated or ideal value for the controller.
Also, the starting-up setting means proposed in the aforementioned patent, which supplies a specific starting curve for starting up the warp beam drive and thereby replaces the position of the dancer as a nominal or rated value signal, can only to a limited extent eliminate the occurrence of stop marks in the woven fabric.